When division of the zygote reaches the eight-cell stage and the planes of cleavage of the upper four cells line up with those of the bottom four cells so that two tiers of cells result, one directly above the other, the type of cleavage is called:
A. direct cleavage
B. spiral cleavage
C. indirect cleavage
D. protostome cleavage
E. radial cleavage
E. radial cleavage
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The bitter receptor hTAS2R38 is activated by glucosinolates found in plants such as turnips and broccoli. The gene variant a person has determines how sensitive their neurons are to these compounds. What would you predict for people who have the high-sensitivity variant of hTAS2R38?
Unlike sweet, salty, sour, or umami, the "bitter" category of tastants includes wide structural variety of detected molecules. Multiple receptors are required to sense the different bitter tastants. What do they have in common? Bitter taste is thought to have evolved as a warning system for toxic compounds. A. They will not easily digest turnips and broccoli. B. They will have to eat more turnips and broccoli to get the same flavor. C. They will dislike turnips and broccoli. D. They will become allergic to turnips and broccoli. Clarify Question What is the key concept addressed by the question? What type of thinking is required? Gather Content What do you already know about taste receptors? What other information is related to the question? Choose Answer Given what you now know, what information is most likely to produce the correct answer? Reflect on Process Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
Where are petioles located?
a. at the end of a stem b. between the leaf and stem c. between adjacent nodes d. within vascular bundles
Which of the following is not a process in the scientific method?
A. Belief in a preconceived idea B. Laboratory experimentation C. Formulation of a hypothesis D. Development of a theory E. Systematic observation
Ca3(PO4)2 represents a(n)
A. element. B. atom. C. mixture. D. isotope. E. compound.